Yellow Starthistle, Centaurea
solstitialis L., non-native- a dicot in the Asteraceae family
-

One of the major goals of the Four Creeks Chapter of
the Sierra Los Tulares Land Trust, which manages Kaweah Oaks Preserve,
is to control invasive weed species. On the top of this list is yellow
star thistle. We have used several methods in the past including physical
removal, flail mowing, and spot treatment with chemicals. We may have some
small scale experiments using fire in the future. We have also been cooperating
with the Agricultural Commissioner's Office's Biological Control Program
on the release of insects that destroy the flower head of yellow star thistle
and/or the seeds.

Control of this weed will be an on-going process that
will not be accomplished in one year or even a few years. It will
require long-term dedication and, most likely, there will be years when
control is better than others.

Carol Frate; President, Four Creeks Chapter

Yellow starthislte flower on left, grows in great colonies on west
meadow.

YST inside outlined areaYellow Star Thistle grows to 3 feet tall in the summertime. It is stiff
and well branched, with bright sunflower yellow flowers. Flowers
have sharp spikes radiating from its base.
- thus the name "Star" thistle.